"glen herrmannsfeldt" <gah@ugcs.caltech.edu> wrote in message> Hans-Peter Diettrich <DrDiettrich1@aol.com> wrote:>> [snip...] [snip...] [snip...]>>> For that reason some (Texas Instruments?) processors implemented a>> register stack, decades ago, with its stack pointer adjusted according>> to the number of registers used in a subroutine. This stack could be>> moved into the CPU nowadays, eliminating the need for saving registers>> in external memory.>> If I remember the TMS9900, the registers were in memory, so that> pointer just changed where in memory they were.

The TMS9900 did allocate the register "file" in memory, with a pointer
in the CPU to indicate the position of the register file. Some
versions of the chip had some on-board RAM that could be used for
register allocation. This RAM was faster to access and would speed
along execution.